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SOLVE THE SYSTEM ALGEBRAICALLY

SOLVE THE SYSTEM ALGEBRAICALLY-example-1
User Raviteja
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1 Answer

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Answer: (4,3) and (-1,8)

Explanation:

Before I solve the system, I am going to rewrite it to make it easier for me to understand it.


y=x^2-4x+3\\y=-x+7

Notice that f(x) and g(x) have been changed into y. The reason is because f(x) and g(x) are the same and stand for y, but we only use f and g to distinguish between the 2 equations. We can use equal values to solve.


x^2-4x+3=-x+7 [add both sides by x]


x^2-3x+3=7 [subtract both sides by 7]


x^2-3x-4=0 [factor]


(x-4)(x+1)=0

Notice that x-4=0 and x+1=0. This means the solutions are x=4 and x=-1.

To find the actual full solution, we have to plug those points back into the original equations.


-(4)+7=-4+7=3\\-(-1)+7=1+7=8

Therefore, the solutions to this system are (4,3) and (-1,8).

User Jammon
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